Polycarbonate Compositions Containing Titanium Dioxide and Epoxy Group-Containing Triacylglycerol

Abstract

The present disclosure is direct to titanium dioxide-containing, polycarbonate-based thermoplastic compositions that contain epoxidized triacylglycerol. These compositions are suitable for reflectors. The compositions described in the present disclosure have an improved reflectance and a lower yellowness index as compared to reference compositions that do not contain epoxidized triacylglycerol. The epoxidized triacylglycerol may be in the form of epoxidized soybean oil.

1 . A thermoplastic composition, containing
 A) aromatic polycarbonate,   B) titanium dioxide,   C) epoxidized triacylglycerol.   
     
     
         2 . The thermoplastic composition as claimed in  claim 1 , containing
 A) 59.99% by weight to 96.99% by weight of aromatic polycarbonate,   B) 3.0% by weight to 40.0% by weight of titanium dioxide,   C) 0.01% by weight to 5.0% by weight of epoxidized triacylglycerol,   wherein the reported amounts in % by weight are based on the total weight of the composition.   
     
     
         3 . The thermoplastic composition as claimed in  claim 1 , containing
 A) 69.99% by weight to 96.99% by weight of aromatic polycarbonate,   B) 3.0% by weight to 30.0% by weight of titanium dioxide,   C) 0.01% by weight to 2.0% by weight of epoxidized triacylglycerol,   D) 0.0% by weight to 1.0% by weight of heat stabilizer,   E) 0.0% by weight to 0.5% by weight of flame retardant selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives and combinations thereof and   F) 0.0% by weight to 10.0% by weight of further additives,   wherein the reported amounts in % by weight are based on the total weight of the composition.   
     
     
         4 . The thermoplastic composition as claimed in  claim 1 , wherein the composition contains
 A) 77.945% by weight to 96.945% by weight of aromatic polycarbonate,   B) 3.0% by weight to 22% by weight of titanium dioxide,   C) 0.05% by weight to 0.8% by weight of epoxidized triacylglycerol,   D) 0.005% by weight to 0.5% by weight of heat stabilizer,   E) 0.0% by weight to 0.5% by weight of flame retardant selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives and combinations thereof and   F) 0.0% by weight to 3.0% by weight of further additives,   wherein the reported amounts in % by weight are based on the total weight of the composition.   
     
     
         5 . The thermoplastic composition as claimed in  claim 1 , wherein the thermoplastic composition consists of
 A) 77.945% by weight to 96.945% by weight of aromatic polycarbonate,   B) 3.0% by weight to 22% by weight of titanium dioxide,   C) 0.05% by weight to 0.8% by weight of epoxidized triacylglycerol introduced into the composition in the form of epoxidized soybean oil,   D) 0.005% by weight to 0.5% by weight of heat stabilizer,   E) 0.0% by weight to 0.5% by weight of flame retardant selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives and combinations thereof and   F) 0.0% by weight to 3% by weight of further additives   and optionally blend partners.   
     
     
         6 . The thermoplastic composition as claimed in  claim 3 , wherein the amount of component E is 0.05% by weight to 0.15% by weight. 
     
     
         7 . The thermoplastic composition as claimed in  claim 1 , wherein the epoxidized triacylglycerol contains a mixture of triesters of glycerol with oleic acid, linoleic acid, linolenic acid, palmitic acid and/or stearic acid. 
     
     
         8 . The thermoplastic composition as claimed in  claim 1 , wherein at least 90% by weight of the C═C double bonds from the carboxylic acid moieties of the triacylglycerols have been completely epoxidized. 
     
     
         9 . The thermoplastic composition as claimed in  claim 1 , wherein component C is introduced into the thermoplastic composition through admixing of epoxidized soybean oil (CAS number 8013-07-8). 
     
     
         10 . The thermoplastic composition as claimed in  claim 3 , wherein at least one anti-drip agent is present as a further additive of component F. 
     
     
         11 . The thermoplastic composition as claimed in  claim 10 , wherein at least 0.1% by weight of anti-drip agents are present. 
     
     
         12 . A molded part made of a thermoplastic composition as claimed in  claim 1 . 
     
     
         13 . The molded part as claimed in  claim 12 , wherein the molded part is a reflector or part of a reflector for an LED illumination unit. 
     
     
         14 . A method to improve reflectance of a titanium dioxide-containing polycarbonate composition comprising providing thereto an epoxidized triacylglycerol. 
     
     
         15 . The method as claimed in  claim 14 , wherein the provision of the epoxidized triacylglycerol improves a yellowness index of the titanium dioxide-containing polycarbonate composition. 
     
     
         16 . The method as claimed in  claim 14 , wherein the epoxidized triacylglycerol is in the form of epoxidized soybean oil.